在Mac上使用Eclipse的HelloWorld

Question

Running the simple HelloWorld.java program below (by clicking run in eclipse)

public class HelloWorld {
   public static void main (String [] args) {
     System.out.println("Hello World");
   }    
}

after installing the latest version of Eclipse on my mac 10.7.2 yields the following error:

Exception in thread "main" java.lang.NoClassDefFoundError: 
Caused by: java.lang.ClassNotFoundException: 
    at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:247)

What do i do?

Answer 1

Sounds like when you tell it to run you have the wrong class file selected

Click on the run icon drop down and select Run Configurations, then make sure you have the right class selected for main class.

Answer 2

使用MacOS随附的默认Java环境为我解决了此问题。